Lock for doors, &amp;c.



C. RIZZO.

LOCK FOR DOORS, &c.

APPUcATloN man FEB. 14,-19ls.

1,210,695. Patented Jan. 2, 1917.

ATTURNEYEL cHAnLEsnIzzo, or BUnFALmNEW YORK.

, LOCK DOORS, &c.

Specification of Letters Patent.

Patented Jan. 2, 1917.

Application led' February 14', 1916.' Serial No. 78,112.`

To all whom it may concern:

Be it known thatl I, CHARLES Rizzo, a citizen of the United States, residing at Buffalo, in the county of Erie and State ofV New York, have invented new and useful Improvements in Locks for. Doors, &c., lof which the following is a specification.

This invention relates to door and window locks of the vclass requiring different move- 'mentsv of the key with a View of rendering it impossible to unlockk the same without knowledge of the particular manner of ma'- nipulating the key.

The object :of'my invention is to simplify the construction' and reducel the cost of manufacture of such locks".

In the accompanyingdrawings: Figure 1 is afragmentary vertical section of a door provided with my improved lock, the front plate ofthe lock' being partly broken away; Fig. 2 is a similarfview,tlo'oking inthe opposite direction, with the rear plate removed. Fig. 3 is a transverse vertical section on line 3 3, Fig; 1. Fig. 4 is a horizontal section on line 4;-4', Fig. 2.

Similar characters of reference indicate corresponding parts in the several views.

1 indicates the body of the door, 2 the mortise' in which the elements of the lock are confined, 3 the opening for the key, and 4 the usual plate secured to the edge of the door for covering said mortise. Y

In thezexample shown in the drawings, the lock'is adapted to be'manip'ulated from the outside, only.

5 indicates a plate extending practically throughout the length of the mortise 2 and forming the frontiI wall of the lock case or frame. This plate is provided with a key hole 6 having a branch slot 6a extending laterally from its eye, and arrangedsubstantially at right angles to its-main vertical portion, forming a substantially L-shaped keyhole. A locking bolt 7 is arranged horizontally on the rear side of the plate 5 and guided thereon by straps or guides 8, the bolt Abeing adapted to pass through the usual opening 1n the face plate 4. Intermediate its ends, this bolt is provided in its upper edge with a series of ratchet teeth 9, two being shown in the drawings, while in its lower edge it is provided with a plurality of operating teeth or projections 10, the purpose of which will be `presently described. A suitable detent or pawl 11, which may be constructed in the form of a flat spring, as

shown, is fastened to the upper portion of the plate 5 by rivets 12 or other suitable means. The lower portion of this detent is recessed or cutV away, to form a tooth or shoulder 13 which is adapted to engage the ratchet teethy 9, and beyond this tooth the detent is provided with a releasing finger 14 projecting downwardly a suitable distance below the teeth 10 of the looking bolt. This detent and said ratchet teeth constitute the maink locking means of the bolt when projected.

Arranged in rear of the plate 5 and spaced therefrom is an upright rear plate 15 having its lower portion bent forwardly and downwardly and fastened to said plate.` These plates form the case or frame structure of thel lock.r Projecting outwardly from the rear plate 15 a-nd arranged in line with the eye of the lkey-hole 6, is a stud 1G adapted to enter ank opening in the front end ofthe key 17. Two wards or segmental ribs 18, 19 are arranged on the inner walls of the plates 5 andll, respectively, concentrically with the eye of the key-hole. Asshown in Fig. 1, the radius'of the ward 18 is smaller than that of the ward 19. The bit ofthe key has corresponding clefts or grooves 20, 21, which receive said wards,` thereby preventing the lock from being opened except by its own proper key. i

A locking catch 22 preferably in the form of a fia-t strip of spring metal is secured` to the upper portion of the plate 5 and eX- tends downwardly a sufficient distance to coverI oroverlap the horizontal'branch 6a of the-key-hole 6. This catchisv provided on its inner face with a locking, pin 23 which freely passes through an opening 24: in the plate 5 andis adaptedto interlock with an aperture 25 in the locking bolt when the latter has reached its eXtreme locking or shot position, as shownin Fig. 5, thereby preventing retraction of the bolt unless released by withdrawal of said pin. This catch forms an auxiliarylock for said bolt.

The inner end of the locking bolt is provided with a pin or projection 26 which is arranged to engage a spring 27 suitably fastened at its upper end to the arm 28. This spring is strained when the bolt is fully projected and tends to retract it .when released by the catch 28.

When the bolt is projected, the releasing linger of the detent extends into the path of circular movement of the key-bit, so as to be tripped by it and raise the detent tooth out of engagement with the teeth 9 of the bolt.

When the bolt is in the unlocked or retracted position shown in Fig. 1, the detent tooth 13 bears on the bolt in front'of its series of ratchet teeth 9 and the projection 26 of the bolt is located some distance behind the spring 27. When it is desired to lock the door, the key is placed in the key-hole and engaged with-the stud 16. It is then turned counter-clockwise, referring to Fig. .1, whereby its bit engages the first of the lower teeth 10 of the locking-bolt, advancing the latter the Vdistance of one tooth. The key is then again rotated to advance the bolt another step by engaging its second tooth 10. If the bolt has more than two of such teeth,

Y this operation is repeated until the key bit has engaged and cleared the last tooth, when the bolt will be fully thrown and the pin 23 of the spring catch will enter the opening 25 of the bolt and lock it in that position, as shown in Figs. 2 and l5. Beforevthe bolt reaches the limit of its outward movement, its pin 26v engages and strainsfthe spring 27. y

To unlock the door, the key is inserted as described and turned to bring its bit in register with the lateral branch 6 of the keyhole. While in. this positon, the key is pulled outwardly, thereby causing its bit to y enter said branch and bear against the spring catch 22 and withdraw its pin from the aperture 25 of the bolt. As soon as the bolt is thus released, the spring 27 shifts the bolt inward until its rearmost ratchet tooth 9 abuts against the tooth 13 of the detent pawl 11, this movement of the bolt being sufficient to shift its locking aperture out of register with the pin of the catch; The bolt is then retracted by completely turning the key clockwise, onceforevery tooth 10 of the bolt, the latter being shifted inwardly a step every time the key-bit engages one of said teeth, and the bolt being fully withdrawn when the bit clears the last tooth. In this unlocking operation, the key-bit, before engaging the teeth 10 of the bolt, trips the releasing finger 14C of the detent 11, lifting its tooth or shoulder 13 out of engagement with the ratchet teeth 9, and permitting the bolt to be moved inward by the key-bit, as above described. i

Owing to the peculiar construction of this lock and the particular manipulation of the key required to release the bolt, an unauthorized person, such as a burglar, would ind it exceedingly difficult to unlock the door, even with a proper key. The key-hole visible on the face of the door is of the ordinary form having a simple slot and an eye and gives no suggestion of the concealed and differently-shaped key-hole in the plate 5 with which the visible key-hole coperates. In the example shown in the drawings, the locking bolt has three shifting teeth 10, but it may obviously be provided with a greater or less number of teeth andthe lock may be modified in other respects within the scope of the appended claim.

If desired, a burglar ala-rm may be combined with the lock to* give warning in case an unauthorized person should by chance or otherwise succeed in releasing the bolt. .The alarm shown in the drawings comprises a trigger-block 29 to which is pivotedva trigger 30 adapted to .explode a cartridge 31 arranged in an opening in said blockrand havinga suitable spring 32.

The -trigger is cocked by hand and `is automatically pulled by a trip arm 34 carried'by the locking bolt and ladapted to engage an upright tappet 35 on the heel ofthe trigger. As the door has to be -cut away to allow the necessary movement of the trigger, a suitable closure 36 in the form of `a hinged cover may be attached thereto, as shown'.

I claim as my inventior: A lock, comprising a supporting plate having a key-hole provided with a branchslot, a locking bolt provided with a series of detent teeth and a series of operatingteeth,fthe latter adapted to be engaged by the bit of a keyV inserted in said hole, a detent pawl engaging Isaid Vdetent tceth and-having a releasing member arranged adjacent to said key-hole-in -position to be engaged by the bit of the-key, a catch arranged to interlock with said bolt in the fully-projected position of the bolt, a portion of said catch extending acrossfsaid branch-slot to be engaged by the key-bit, and automatic means for partly'retracting the bolt upon the disengagement of said catch therefrom. 'f CHARLES RIZZO.

Copiesof this patent may be obtainedfor five cents each, by addressing the vvGommissionerof Patents,

' Vashington,V 1 C. i 

